1. Field of the Invention
The present invention relates generally to the entry of passwords, codes or identification numbers into data processing systems, Automated Teller Machines (ATMs), locks, or other security or access control type devices. More particularly, the invention relates to the checking of the rhythm and tempo used for entry of the password, code or identification number.
2. Description of Related Art
It is known that IBM Technical Disclosure Bulletin v 30, n.5, October 1987, p.258, entitled “Passwords for Computer Systems and Cipher Locks Containing Rhythm Patterns” discloses the use of a password with timing constraints such as the pauses between key-presses or the duration of the key-press being added. The pauses or duration are predefined and may be either “long” or short” and may be either relative to each other or absolute values.
U.S. Pat. No. 4,621,334 discloses a personal identification apparatus in which a mean time between keystrokes is used to determine whether a person attempting to gain access is the person who should be granted access to the system.
U.S. Pat. No. 4,805,222 discloses a method of verifying a person's identity by measuring the average inter-character time between successive pairs of keystrokes and comparing this with a pre-stored sample.
U.S. Pat. No. 5,557,686 discloses a user verification system in which vectors are constructed from user inputted samples and a neural network is used to determine whether the user inputted samples are similar to a sample entered for user verification.
U.S. Pat. No. 5,721,765 discloses a security system in which digits of an identification number are separated into two or more groups that must be entered with a predetermined time delay between each of the two or more groups.
U.S. Pat. No. 6,151,593 discloses a neural network which compares a timing vector extracted from the keystrokes a user has typed in with a training set to authenticate the identity of the user.
It would be desirable to allow entry of a password, code or identification number according to a rhythm and tempo defined by the user entering the password, code or identification number during a learning period.